Quick Chat returns 403 while ChatGPT Work tasks and Codex work normally

What version of the Codex App are you using (From “About Codex” dialog)?

26.707.51957

What subscription do you have?

ChatGPT Plus

What platform is your computer?

Darwin 24.6.0 arm64 arm

What issue are you seeing?

Summary

Quick Chat in the new ChatGPT desktop app always fails with:

Request failed with status 403

The issue only affects Quick Chat opened from the left sidebar "Chat" button.

Other features work normally:

• ChatGPT Work tasks can send and receive messages
• Codex tasks work normally
• ChatGPT works normally in the browser
• The same account is used in all cases

Steps to reproduce

1. Open the ChatGPT desktop app on macOS.
2. Select "ChatGPT Work" from the top-left mode selector.
3. Click "Chat" in the left sidebar.
4. A Quick Chat window opens on the right.
5. Send a simple message such as test.

Actual result

The message is not completed and the Quick Chat window displays:

Request failed with status 403

Expected result

Quick Chat should send the message and return a normal response.

Troubleshooting already attempted

• Fully quit the desktop app with Command + Q
• Reopened the app
• Signed out and signed back in
• Retried Quick Chat
• Confirmed that ChatGPT works normally in the browser
• Confirmed that Codex conversations work normally
• Confirmed that ChatGPT Work tasks work normally

The issue still occurs only in Quick Chat.

Additional observations

A new task created under ChatGPT Work successfully sends test and receives a response.

This suggests that the account, subscription, general network connection, ChatGPT Work access, and Codex access are functioning normally. The failure appears isolated to the Quick Chat feature or its authentication/authorization path.

Error message

Request failed with status 403

What steps can reproduce the bug?

1. Open the ChatGPT desktop app on macOS.

1. In the top-left mode selector, select ChatGPT Work.

1. Click Chat in the left sidebar.

1. A Quick Chat window opens on the right side.

1. Enter a simple message such as:

test

1. Send the message.

Actual result

The Quick Chat window returns the following error:

Request failed with status 403

The message cannot be completed.

Additional information

The issue only affects Quick Chat.

The following features work normally with the same account and network:

• ChatGPT Work tasks can send and receive messages normally.
• Codex tasks can send and receive messages normally.
• ChatGPT works normally in the browser.

I have already tried:

• Fully quitting the desktop app with Command + Q.
• Reopening the app.
• Signing out and signing back in.
• Retrying Quick Chat.

The issue still occurs.

No code snippet, session ID, token limit usage, or context window usage is applicable to this issue.

What is the expected behavior?

_No response_

Additional information

<img width="1185" height="917" alt="Image" src="https://github.com/user-attachments/assets/917d2f3c-234d-4cd5-8e25-a84aafa2b622" />